The Howard T. Odum Florida Springs Institute (FSI) has found an alarming invasion of Blue tilapia that has replaced the native fish population in Silver Springs State Park based on a recent survey.
In 2019, Blue tilapia made up 25% of the fish biomass in Silver Springs but as of July this year numbers jumped to 86%.
According to Dr. Knight, “Native fish species are only at 41% of their population sizes prior to the Rodman/Kirkpatrick Dam’s completion in 1968, when populations collapsed.”
A 2021 study published in Science magazine found that biodiversity of over 50% of the world’s rivers has been seriously impacted by dams and the introduction of non-native fish species.
Currently, the St. Johns River Water Management District is collecting feedback from local community members and stakeholders regarding the Kirkpatrick Dam and Rodman Reservoir, with a focus on interests surrounding the dam’s environmental and economic impact. The form will be open until end of day Oct. 22.
Click this link to open the survey: https://floridaswater.formstack.com/forms/rodman
References:
- Invasive blue tilapia now make up 86% of fish at Silver Springs in Marion County, Danielle Johnson, Ocala Star-Banner
https://www.ocala.com/story/news/environment/2021/09/18/invasive-blue-tilapia-represent-eighty-six-percent-total-fish-population-silver-springs/8337132002/ - Human impacts on global freshwater fish biodiversity, Science • 19 Feb 2021 • Vol 371, Issue 6531 • pp. 835-838
https://www.science.org/doi/10.1126/science.abd3369 - Blue Tilapia FWC https://myfwc.com/wildlifehabitats/profiles/freshwater/blue-tilapia/
- St. Johns Riverkeeper Action Alert https://www.stjohnsriverkeeper.org/urgent-action-alert-for-the-ocklawaha/
Source: UF/IFAS Pest Alert
